1. Field of the Invention
The present invention relates to a device for holding and retaining cables. More specifically the invention relates to a mechanism having resilient, internal rib projections for centering a cable within a retainer housing.
2 Description of the Related Art
In today's wide variety of electrical devices, it is common to have boxes or other housings with cable ports for receiving cable. The cable port is an entry point for cable as well as undesirable elements such as insects, small animals, wind, and rain. Accordingly, many methods have been used to seal the cable port and electrical box from these nuisances.
Sealants such as caulking have been used, but in recent years have been disfavored. Caulking is difficult to work with, does not clean up easily, and takes substantial removal effort in the event repairs are needed. Currently, heat-shrink or even cold-shrink tubing are preferred for their ease of use and relatively clean application.
Heat-shrinkable tubing is placed around the cable port and cable at the interface thereof. Heat is then applied to the tubing, causing it to conform to the shape of the cable and cable port. The space between the cable and the cable port is, thus, sealed. As the tubing is shrunk, heat must be applied evenly or one portion of the tubing will shrink before the remaining portions. Uneven heating and shrinking lead to aconcentric, noncentered positioning of cable within the cable port.
Similarly, cold shrinkable tubing may also be used. Typically, an expanded tube, maintained in that state by a rigid core, is placed around the cable port and cable at the interface thereof. Once in position, the rigid core is removed and shrinkable tubing to conforms to the shape of the cable port and cable, just as in the heat-shrinkable variety.
The recurring problem in both of these systems concerns the aconcentric enclosing of cable passing through the cable port. When the shrinkable tubing is applied, the cable must be held in a central position in order to obtain the optimal seal. When uncentered, the cable causes the shrinkable tubing to stretch and conform asymmetrically. The asymmetrical nature of the tubing forms an inferior seal and results in stresses on the cable and the shrinkable tubing. Misalignment of the cable within the electrical housing may also result.
The shrinkable tubing has been favored because it easily adapts to the wide range of shapes and diameters of available cable. In order to limit stress and cable misalignment and achieve a better seal, it is desirable to ensure that the cable is centered within the cable port and shrinkable tubing.